Microwave edge guide mode signal splitter and combiner

Abstract

A broad-band microwave waveguide radio frequency splitter and combiner (70 and 100) can be realized by using TEM mode wave propagation to edge guide mode wave propagation conversion performed by magnetically biased material (16) and directionally opposed magnetic fields (20 and 22) and a waveguide such as a microstrip (10) or a stripline (50) to spatially separate a TEM mode signal into two or more components.

What is claimed is: 
     
       1. A radio frequency signal combiner having at least first and second input ports and an output port, electrically adding radio frequency signals at said first and second input ports together to produce an output signal at said output port, said combiner comprises of: a substantially planar transmission line comprised of: a.) a substantially planar ground layer of conductive material having first and second sides;   b.) a substantially planar layer of magnetically biasable material having first and second side, said second side of said magnetically biasable material being coupled to said first side of said ground layer; and   c.) a signal layer comprised of a substantially planar layer of electrically conductive material also having first and second sides said second side of said signal layer being coupled to said first side of said magnetically biasable material:     first converter converting TEM mode waves to edge-guided mode waves comprised of a first localized magnetic field extending substantially orthogonally through said magnetically biasable material, said first magnetic field being substantially isolated to a first portion of said planar transmission line, said first converter having an input and an output;   second converter converting TEM mode waves to edge-guided mode waves comprised of a second localized magnetic field extending through said magnetically biasable material said second magnetic field extending through said magnetically biasable material said second magnetic field being directionally opposed to said first magnetic field where said first and second magnetic fields extend through said magnetically biasable material, said second converter having an input and an output;   combiner means having inputs coupled to the outputs of said first and second converter means, for coupling and combining edge-guided mode propagating waves from said first and second converter means to a single signal at an output of the combiner means.   
     
     
       2. The radio frequency signal combiner of claim 1 where said magnetically biased material includes ferrite. 
     
     
       3. The radio frequency signal combiner of claim 1 where said magnetically biased material includes zinc manganese. 
     
     
       4. The radio frequency signal combiner of claim 1 where said first and second magnetic fields are of substantially equal relative field strength. 
     
     
       5. The radio frequency signal combiner of claim 1 where said first and second magnetic fields are of substantially unequal relative field strength. 
     
     
       6. A radio frequency signal splitter having an input port and at least first and second outputs electrically splitting a radio frequency signal at said input into at least two output signals, said splitter comprised of: a length of substantially planar waveguide transmission line having a length and width and comprised of at least two substantially planar and substantially parallel conductive layers coupled to the upper and lower surfaces of at least one layer of magnetically biased material that extends throughout the length and width of said transmission line, said transmission line having a first induced and localized magnetic field with a first directional orientation that is substantially orthogonal to said substantially parallel conductive layers and that extends through said magnetically biasable material, said length of transmission line having a second localized induced magnetic field with a second directional orientation opposite said first directional orientation, said second magnetic field also substantially orthogonal to and extending through said magnetically biasable material but being through a second portion of said length of transmission line, said first and second magnetic fields being substantially isolated form each other and being located to convert and separate a TEM mode wave input at said input port into at least first and second edge-guide mode waves that travel in the same relative direction and to urge said first and second edge-guide mode waves toward opposing sides of said planar waveguide transmission line and toward said first and second output ports;   first means for coupling said first edge-guided mode propagating wave to the first output port;   second means for coupling said second edge-guided mode propagating wave to the second output port.   
     
     
       7. The radio frequency signal splitter of claim 6 where said magnetically biased material includes ferrite. 
     
     
       8. The radio frequency signal splitter of claim 6 where said first and second magnetic fields are of substantially equal relative field strength throughout substantially equal regions of said means for converting TEM propagating waves. 
     
     
       9. The radio frequency signal splitter of claim 6 where said first and second magnetic fields are of unequal relative field strength throughout substantially equal regions of said means for converting TEM propagating waves. 
     
     
       10. The radio frequency signal splitter of claim 6 where said first and second magnetic fields are of equal relative field strength throughout unequal regions of said means for converting TEM propagating waves. 
     
     
       11. A radio frequency signal splitter having an input and at least first and second outputs electrically splitting a radio frequency signal at said input into at least two, substantially equal magnitude output signals comprised of: a length of waveguide transmission line having a substantially rectangular cross-section, said length of waveguide transmission line having at least two substantially planar, continuous and substantially parallel conductive layers on the upper and lower surfaces of said rectangular cross sectioned waveguide, said length of transmission line having a first end coupled to a signal source and a second end coupled to a signal load, said conductive layers separated by at least one layer of ferrite extending throughout the length of transmission line, said length of transmission line having a first induced magnetic field throughout a first portion of said transmission line having a first directional orientation substantially orthogonal to said substantially parallel conductive layers extending through said conductive layers, said length of transmission line having a second induced magnetic field throughout a second portion of said transmission line with a second directional orientation opposite said first directional orientation, said second induced magnetic field also substantially orthogonal to and through said substantially parallel conductive layers, the presence and orientation of said first and second directions being chosen to separate a TEM mode wave into first and second edge-guide mode propagating waves that travel in the same relative direction and to urge said first and second edge-guide second magnetic field also substantially orthogonal to and extending through mode propagating waves toward opposing sides of said rectangular cross-sectioned waveguide that are orthogonal to the upper and lower surfaces of said waveguide; and   first and second divergent waveguide sections coupled to said second end of the length of waveguide transmission line such that said first and second edge-guide mode propagating waves urged toward opposing sides of said rectangular cross-sectioned waveguide each propagate substantially through one of said first and second divergent waveguide sections.